Epidemiological aspects of Toxoplasma gondii infection in riverside communities in the Southern Brazilian Amazon

• Main Authors: Sérgio Neto Vitaliano, Gabriel Maciel de Mendonça, Felipe Amsterdam Maia de Sandres, Juliana de Souza Almeida Aranha Camargo, Paulo de Tarso, Sérgio de Almeida Basano, Jéssica Carolinne Damasceno e Silva, Viviane Krominski Graça de Souza, Glenci Cartonilho, Alexandre Thomé da Silva de Almeida, Solange Maria Gennari, Luís Marcelo Aranha Camargo
• Format: Article
• Language: English
• Published: Sociedade Brasileira de Medicina Tropical (SBMT) 2015-06-01
• Series: Revista da Sociedade Brasileira de Medicina Tropical
• Subjects: Toxoplasma gondii; Riverside communities; Amazon; Purus River; Epidemiology
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0037-86822015000300301&lng=en&tlng=en

INTRODUCTION: Toxoplasma gondii infection is widely prevalent in humans and other animals worldwide. Information on the prevalence of T. gondii infection is scarce in some regions of Brazil, including riverside communities along the Amazon River basin. M METHODS: The prevalence of T. gondii in 231 people, aged 1-85 years, who were living in four riverside communities along the Purus River, Lábrea, State of Amazonas, Brazil, was determined. Antibodies against T. gondii were assayed using a commercial enzyme-linked immunosorbent assay (ELISA) kit. The hearts and brains of 50 chickens, which were raised free-range in the communities, were pooled according to the community of origin and bioassayed in mice. The isolates were genotyped using polymorphisms at 12 nuclear markers (SAG1, 5' and 3'-SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico and CS3). RESULTS: The overall seroprevalence of T. gondii was 56.7% (131/231). IgG antibodies were presented by 117 (89.3%) and IgM by 14 (10.7%) of the 131 positive individuals. No association between age group and gender with prevalence was observed (chi-square test, p > 0.05); however, the comparison between localities showed that the seroprevalence of T. gondii was significantly lower among the individuals living in the Boca do Ituxi (p < 0.05) community. Five isolates of T. gondii were obtained in the mouse bioassay, and genotyping revealed two complete genotypes that had not been described previously and three mixed isolates. CONCLUSIONS: These results support previous findings that T. gondii population genetics are highly diverse in Brazil and that T. gondii infection is active in these riverside communities.